// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/public/app/content_main_runner.h"

#include <stddef.h>
#include <stdlib.h>
#include <string.h>

#include <memory>
#include <string>
#include <utility>

#include "base/allocator/allocator_check.h"
#include "base/allocator/allocator_extension.h"
#include "base/at_exit.h"
#include "base/base_switches.h"
#include "base/command_line.h"
#include "base/debug/debugger.h"
#include "base/debug/stack_trace.h"
#include "base/feature_list.h"
#include "base/files/file_path.h"
#include "base/i18n/icu_util.h"
#include "base/lazy_instance.h"
#include "base/logging.h"
#include "base/macros.h"
#include "base/memory/scoped_vector.h"
#include "base/metrics/field_trial.h"
#include "base/metrics/histogram_base.h"
#include "base/metrics/statistics_recorder.h"
#include "base/path_service.h"
#include "base/process/launch.h"
#include "base/process/memory.h"
#include "base/process/process.h"
#include "base/process/process_handle.h"
#include "base/profiler/scoped_tracker.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/trace_event/trace_event.h"
#include "build/build_config.h"
#include "components/tracing/browser/trace_config_file.h"
#include "components/tracing/common/trace_to_console.h"
#include "components/tracing/common/tracing_switches.h"
#include "content/app/mojo/mojo_init.h"
#include "content/browser/browser_main.h"
#include "content/browser/gpu/gpu_process_host.h"
#include "content/browser/renderer_host/render_process_host_impl.h"
#include "content/browser/utility_process_host_impl.h"
#include "content/common/set_process_title.h"
#include "content/common/url_schemes.h"
#include "content/gpu/in_process_gpu_thread.h"
#include "content/public/app/content_main.h"
#include "content/public/app/content_main_delegate.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/common/content_client.h"
#include "content/public/common/content_constants.h"
#include "content/public/common/content_paths.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/main_function_params.h"
#include "content/public/common/sandbox_init.h"
#include "content/public/gpu/content_gpu_client.h"
#include "content/public/renderer/content_renderer_client.h"
#include "content/public/utility/content_utility_client.h"
#include "content/renderer/in_process_renderer_thread.h"
#include "content/utility/in_process_utility_thread.h"
#include "ipc/ipc_descriptors.h"
#include "media/base/media.h"
#include "ppapi/features/features.h"
#include "ui/base/ui_base_paths.h"
#include "ui/base/ui_base_switches.h"

#ifdef V8_USE_EXTERNAL_STARTUP_DATA
#include "gin/v8_initializer.h"
#endif

#if defined(OS_WIN)
#include <cstring>
#include <malloc.h>

#include "base/trace_event/trace_event_etw_export_win.h"
#include "base/win/process_startup_helper.h"
#include "sandbox/win/src/sandbox_types.h"
#include "ui/base/win/atl_module.h"
#include "ui/display/win/dpi.h"
#elif defined(OS_MACOSX)
#include "base/mac/scoped_nsautorelease_pool.h"
#include "base/power_monitor/power_monitor_device_source.h"
#include "content/app/mac/mac_init.h"
#include "content/browser/mach_broker_mac.h"
#include "content/common/sandbox_init_mac.h"
#endif // OS_WIN

#if defined(OS_POSIX)
#include <signal.h>

#include "base/posix/global_descriptors.h"
#include "content/public/common/content_descriptors.h"

#if !defined(OS_MACOSX)
#include "content/public/common/zygote_fork_delegate_linux.h"
#endif
#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
#include "content/zygote/zygote_main.h"
#endif

#endif // OS_POSIX

#if defined(USE_NSS_CERTS)
#include "crypto/nss_util.h"
#endif

namespace content {
extern int GpuMain(const content::MainFunctionParams&);
#if BUILDFLAG(ENABLE_PLUGINS)
#if !defined(OS_LINUX)
extern int PluginMain(const content::MainFunctionParams&);
#endif
extern int PpapiPluginMain(const MainFunctionParams&);
extern int PpapiBrokerMain(const MainFunctionParams&);
#endif
extern int RendererMain(const content::MainFunctionParams&);
extern int UtilityMain(const MainFunctionParams&);
} // namespace content

namespace content {

namespace {

    // This sets up two singletons responsible for managing field trials. The
    // |field_trial_list| singleton lives on the stack and must outlive the Run()
    // method of the process.
    void InitializeFieldTrialAndFeatureList(
        std::unique_ptr<base::FieldTrialList>* field_trial_list)
    {
        const base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();

        // Initialize statistical testing infrastructure.  We set the entropy
        // provider to nullptr to disallow non-browser processes from creating
        // their own one-time randomized trials; they should be created in the
        // browser process.
        field_trial_list->reset(new base::FieldTrialList(nullptr));

        // Ensure any field trials in browser are reflected into the child
        // process.
#if defined(OS_POSIX)
        // On POSIX systems that use the zygote, we get the trials from a shared
        // memory segment backed by an fd instead of the command line.
        base::FieldTrialList::CreateTrialsFromCommandLine(
            command_line, switches::kFieldTrialHandle, kFieldTrialDescriptor);
#else
        base::FieldTrialList::CreateTrialsFromCommandLine(
            command_line, switches::kFieldTrialHandle, -1);
#endif

        std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
        base::FieldTrialList::CreateFeaturesFromCommandLine(
            command_line, switches::kEnableFeatures, switches::kDisableFeatures,
            feature_list.get());
        base::FeatureList::SetInstance(std::move(feature_list));
    }

} // namespace

#if !defined(CHROME_MULTIPLE_DLL_CHILD)
base::LazyInstance<ContentBrowserClient>
    g_empty_content_browser_client = LAZY_INSTANCE_INITIALIZER;
#endif //  !CHROME_MULTIPLE_DLL_CHILD

#if !defined(CHROME_MULTIPLE_DLL_BROWSER)
base::LazyInstance<ContentGpuClient>
    g_empty_content_gpu_client = LAZY_INSTANCE_INITIALIZER;
base::LazyInstance<ContentRendererClient>
    g_empty_content_renderer_client = LAZY_INSTANCE_INITIALIZER;
base::LazyInstance<ContentUtilityClient>
    g_empty_content_utility_client = LAZY_INSTANCE_INITIALIZER;
#endif // !CHROME_MULTIPLE_DLL_BROWSER

#if defined(V8_USE_EXTERNAL_STARTUP_DATA) && defined(OS_ANDROID)
#if defined __LP64__
#define kV8SnapshotDataDescriptor kV8SnapshotDataDescriptor64
#else
#define kV8SnapshotDataDescriptor kV8SnapshotDataDescriptor32
#endif
#endif

#if defined(OS_POSIX)

// Setup signal-handling state: resanitize most signals, ignore SIGPIPE.
void SetupSignalHandlers()
{
    // Sanitise our signal handling state. Signals that were ignored by our
    // parent will also be ignored by us. We also inherit our parent's sigmask.
    sigset_t empty_signal_set;
    CHECK_EQ(0, sigemptyset(&empty_signal_set));
    CHECK_EQ(0, sigprocmask(SIG_SETMASK, &empty_signal_set, NULL));

    struct sigaction sigact;
    memset(&sigact, 0, sizeof(sigact));
    sigact.sa_handler = SIG_DFL;
    static const int signals_to_reset[] = { SIGHUP, SIGINT, SIGQUIT, SIGILL, SIGABRT, SIGFPE, SIGSEGV,
        SIGALRM, SIGTERM, SIGCHLD, SIGBUS, SIGTRAP }; // SIGPIPE is set below.
    for (unsigned i = 0; i < arraysize(signals_to_reset); i++) {
        CHECK_EQ(0, sigaction(signals_to_reset[i], &sigact, NULL));
    }

    // Always ignore SIGPIPE.  We check the return value of write().
    CHECK_NE(SIG_ERR, signal(SIGPIPE, SIG_IGN));
}

#endif // OS_POSIX

void CommonSubprocessInit(const std::string& process_type)
{
#if defined(OS_WIN)
    // HACK: Let Windows know that we have started.  This is needed to suppress
    // the IDC_APPSTARTING cursor from being displayed for a prolonged period
    // while a subprocess is starting.
    PostThreadMessage(GetCurrentThreadId(), WM_NULL, 0, 0);
    MSG msg;
    PeekMessage(&msg, NULL, 0, 0, PM_REMOVE);
#endif
#if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
    // Various things break when you're using a locale where the decimal
    // separator isn't a period.  See e.g. bugs 22782 and 39964.  For
    // all processes except the browser process (where we call system
    // APIs that may rely on the correct locale for formatting numbers
    // when presenting them to the user), reset the locale for numeric
    // formatting.
    // Note that this is not correct for plugin processes -- they can
    // surface UI -- but it's likely they get this wrong too so why not.
    setlocale(LC_NUMERIC, "C");
#endif

#if !defined(OFFICIAL_BUILD)
    // Print stack traces to stderr when crashes occur. This opens up security
    // holes so it should never be enabled for official builds.
    if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
            switches::kDisableInProcessStackTraces)) {
        base::debug::EnableInProcessStackDumping();
    }
#if defined(OS_WIN)
    base::RouteStdioToConsole(false);
    LoadLibraryA("dbghelp.dll");
#endif
#endif
}

class ContentClientInitializer {
public:
    static void Set(const std::string& process_type,
        ContentMainDelegate* delegate)
    {
        ContentClient* content_client = GetContentClient();
#if !defined(CHROME_MULTIPLE_DLL_CHILD)
        if (process_type.empty()) {
            if (delegate)
                content_client->browser_ = delegate->CreateContentBrowserClient();
            if (!content_client->browser_)
                content_client->browser_ = &g_empty_content_browser_client.Get();
        }
#endif // !CHROME_MULTIPLE_DLL_CHILD

#if !defined(CHROME_MULTIPLE_DLL_BROWSER)
        base::CommandLine* cmd = base::CommandLine::ForCurrentProcess();
        if (process_type == switches::kGpuProcess || cmd->HasSwitch(switches::kSingleProcess) || (process_type.empty() && cmd->HasSwitch(switches::kInProcessGPU))) {
            if (delegate)
                content_client->gpu_ = delegate->CreateContentGpuClient();
            if (!content_client->gpu_)
                content_client->gpu_ = &g_empty_content_gpu_client.Get();
        }

        if (process_type == switches::kRendererProcess || cmd->HasSwitch(switches::kSingleProcess)) {
            if (delegate)
                content_client->renderer_ = delegate->CreateContentRendererClient();
            if (!content_client->renderer_)
                content_client->renderer_ = &g_empty_content_renderer_client.Get();
        }

        if (process_type == switches::kUtilityProcess || cmd->HasSwitch(switches::kSingleProcess)) {
            if (delegate)
                content_client->utility_ = delegate->CreateContentUtilityClient();
            // TODO(scottmg): http://crbug.com/237249 Should be in _child.
            if (!content_client->utility_)
                content_client->utility_ = &g_empty_content_utility_client.Get();
        }
#endif // !CHROME_MULTIPLE_DLL_BROWSER
    }
};

// We dispatch to a process-type-specific FooMain() based on a command-line
// flag.  This struct is used to build a table of (flag, main function) pairs.
struct MainFunction {
    const char* name;
    int (*function)(const MainFunctionParams&);
};

#if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
// On platforms that use the zygote, we have a special subset of
// subprocesses that are launched via the zygote.  This function
// fills in some process-launching bits around ZygoteMain().
// Returns the exit code of the subprocess.
int RunZygote(const MainFunctionParams& main_function_params,
    ContentMainDelegate* delegate)
{
    static const MainFunction kMainFunctions[] = {
        { switches::kRendererProcess, RendererMain },
#if BUILDFLAG(ENABLE_PLUGINS)
        { switches::kPpapiPluginProcess, PpapiPluginMain },
#endif
        { switches::kUtilityProcess, UtilityMain },
    };

    ScopedVector<ZygoteForkDelegate> zygote_fork_delegates;
    if (delegate) {
        delegate->ZygoteStarting(&zygote_fork_delegates);
        media::InitializeMediaLibrary();
    }

    // This function call can return multiple times, once per fork().
    if (!ZygoteMain(main_function_params, std::move(zygote_fork_delegates)))
        return 1;

    if (delegate)
        delegate->ZygoteForked();

    // Zygote::HandleForkRequest may have reallocated the command
    // line so update it here with the new version.
    const base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
    std::string process_type = command_line.GetSwitchValueASCII(switches::kProcessType);
    ContentClientInitializer::Set(process_type, delegate);

    MainFunctionParams main_params(command_line);
    main_params.zygote_child = true;

    std::unique_ptr<base::FieldTrialList> field_trial_list;
    InitializeFieldTrialAndFeatureList(&field_trial_list);

    for (size_t i = 0; i < arraysize(kMainFunctions); ++i) {
        if (process_type == kMainFunctions[i].name)
            return kMainFunctions[i].function(main_params);
    }

    if (delegate)
        return delegate->RunProcess(process_type, main_params);

    NOTREACHED() << "Unknown zygote process type: " << process_type;
    return 1;
}
#endif // defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)

static void RegisterMainThreadFactories()
{
#if !defined(CHROME_MULTIPLE_DLL_BROWSER) && !defined(CHROME_MULTIPLE_DLL_CHILD)
    UtilityProcessHostImpl::RegisterUtilityMainThreadFactory(
        CreateInProcessUtilityThread);
    RenderProcessHostImpl::RegisterRendererMainThreadFactory(
        CreateInProcessRendererThread);
    GpuProcessHost::RegisterGpuMainThreadFactory(
        CreateInProcessGpuThread);
#else
    base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
    if (command_line.HasSwitch(switches::kSingleProcess)) {
        LOG(FATAL) << "--single-process is not supported in chrome multiple dll browser.";
    }
    if (command_line.HasSwitch(switches::kInProcessGPU)) {
        LOG(FATAL) << "--in-process-gpu is not supported in chrome multiple dll browser.";
    }
#endif // !CHROME_MULTIPLE_DLL_BROWSER && !CHROME_MULTIPLE_DLL_CHILD
}

// Run the FooMain() for a given process type.
// If |process_type| is empty, runs BrowserMain().
// Returns the exit code for this process.
int RunNamedProcessTypeMain(
    const std::string& process_type,
    const MainFunctionParams& main_function_params,
    ContentMainDelegate* delegate)
{
    static const MainFunction kMainFunctions[] = {
#if !defined(CHROME_MULTIPLE_DLL_CHILD)
        { "", BrowserMain },
#endif
#if !defined(CHROME_MULTIPLE_DLL_BROWSER)
#if BUILDFLAG(ENABLE_PLUGINS)
        { switches::kPpapiPluginProcess, PpapiPluginMain },
        { switches::kPpapiBrokerProcess, PpapiBrokerMain },
#endif // ENABLE_PLUGINS
        { switches::kUtilityProcess, UtilityMain },
        { switches::kRendererProcess, RendererMain },
        { switches::kGpuProcess, GpuMain },
#endif // !CHROME_MULTIPLE_DLL_BROWSER
    };

    RegisterMainThreadFactories();

    for (size_t i = 0; i < arraysize(kMainFunctions); ++i) {
        if (process_type == kMainFunctions[i].name) {
            if (delegate) {
                int exit_code = delegate->RunProcess(process_type,
                    main_function_params);
#if defined(OS_ANDROID)
                // In Android's browser process, the negative exit code doesn't mean the
                // default behavior should be used as the UI message loop is managed by
                // the Java and the browser process's default behavior is always
                // overridden.
                if (process_type.empty())
                    return exit_code;
#endif
                if (exit_code >= 0)
                    return exit_code;
            }
            return kMainFunctions[i].function(main_function_params);
        }
    }

#if defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID)
    // Zygote startup is special -- see RunZygote comments above
    // for why we don't use ZygoteMain directly.
    if (process_type == switches::kZygoteProcess)
        return RunZygote(main_function_params, delegate);
#endif

    // If it's a process we don't know about, the embedder should know.
    if (delegate)
        return delegate->RunProcess(process_type, main_function_params);

    NOTREACHED() << "Unknown process type: " << process_type;
    return 1;
}

class ContentMainRunnerImpl : public ContentMainRunner {
public:
    ContentMainRunnerImpl()
        : is_initialized_(false)
        , is_shutdown_(false)
        , completed_basic_startup_(false)
        , delegate_(NULL)
        , ui_task_(NULL)
    {
#if defined(OS_WIN)
        memset(&sandbox_info_, 0, sizeof(sandbox_info_));
#endif
    }

    ~ContentMainRunnerImpl() override
    {
        if (is_initialized_ && !is_shutdown_)
            Shutdown();
    }

    int Initialize(const ContentMainParams& params) override
    {
        ui_task_ = params.ui_task;

#if defined(USE_AURA)
        env_mode_ = params.env_mode;
#endif

        base::EnableTerminationOnOutOfMemory();
#if defined(OS_WIN)
        base::win::RegisterInvalidParamHandler();
        ui::win::CreateATLModuleIfNeeded();

        sandbox_info_ = *params.sandbox_info;
#else // !OS_WIN

#if defined(OS_ANDROID)
        // See note at the initialization of ExitManager, below; basically,
        // only Android builds have the ctor/dtor handlers set up to use
        // TRACE_EVENT right away.
        TRACE_EVENT0("startup,benchmark,rail", "ContentMainRunnerImpl::Initialize");
#endif // OS_ANDROID

        base::GlobalDescriptors* g_fds = base::GlobalDescriptors::GetInstance();
        ALLOW_UNUSED_LOCAL(g_fds);

        // On Android,
        // - setlocale() is not supported.
        // - We do not override the signal handlers so that we can get
        //   stack trace when crashing.
        // - The ipc_fd is passed through the Java service.
        // Thus, these are all disabled.
#if !defined(OS_ANDROID)
        // Set C library locale to make sure CommandLine can parse argument values
        // in correct encoding.
        setlocale(LC_ALL, "");

        SetupSignalHandlers();
        g_fds->Set(kMojoIPCChannel,
            kMojoIPCChannel + base::GlobalDescriptors::kBaseDescriptor);

        g_fds->Set(
            kFieldTrialDescriptor,
            kFieldTrialDescriptor + base::GlobalDescriptors::kBaseDescriptor);
#endif // !OS_ANDROID

#if defined(OS_LINUX) || defined(OS_OPENBSD)
        g_fds->Set(kCrashDumpSignal,
            kCrashDumpSignal + base::GlobalDescriptors::kBaseDescriptor);
#endif // OS_LINUX || OS_OPENBSD

#endif // !OS_WIN

        is_initialized_ = true;
        delegate_ = params.delegate;

        // The exit manager is in charge of calling the dtors of singleton objects.
        // On Android, AtExitManager is set up when library is loaded.
        // A consequence of this is that you can't use the ctor/dtor-based
        // TRACE_EVENT methods on Linux or iOS builds till after we set this up.
#if !defined(OS_ANDROID)
        if (!ui_task_) {
            // When running browser tests, don't create a second AtExitManager as that
            // interfers with shutdown when objects created before ContentMain is
            // called are destructed when it returns.
            exit_manager_.reset(new base::AtExitManager);
        }
#endif // !OS_ANDROID

#if defined(OS_MACOSX)
        // We need this pool for all the objects created before we get to the
        // event loop, but we don't want to leave them hanging around until the
        // app quits. Each "main" needs to flush this pool right before it goes into
        // its main event loop to get rid of the cruft.
        autorelease_pool_.reset(new base::mac::ScopedNSAutoreleasePool());
        InitializeMac();
#endif

        // On Android, the command line is initialized when library is loaded and
        // we have already started our TRACE_EVENT0.
#if !defined(OS_ANDROID)
        // argc/argv are ignored on Windows and Android; see command_line.h for
        // details.
        int argc = 0;
        const char** argv = NULL;

#if !defined(OS_WIN)
        argc = params.argc;
        argv = params.argv;
#endif

        base::CommandLine::Init(argc, argv);

        base::EnableTerminationOnHeapCorruption();

        // TODO(yiyaoliu, vadimt): Remove this once crbug.com/453640 is fixed.
        // Enable profiler recording right after command line is initialized so that
        // browser startup can be instrumented.
        if (delegate_ && delegate_->ShouldEnableProfilerRecording())
            tracked_objects::ScopedTracker::Enable();

        SetProcessTitleFromCommandLine(argv);
#endif // !OS_ANDROID

        int exit_code = 0;
        if (delegate_ && delegate_->BasicStartupComplete(&exit_code))
            return exit_code;

        completed_basic_startup_ = true;

        const base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
        std::string process_type = command_line.GetSwitchValueASCII(switches::kProcessType);

        // Initialize mojo here so that services can be registered.
        InitializeMojo();

#if defined(OS_WIN)
        if (command_line.HasSwitch(switches::kDeviceScaleFactor)) {
            std::string scale_factor_string = command_line.GetSwitchValueASCII(
                switches::kDeviceScaleFactor);
            double scale_factor = 0;
            if (base::StringToDouble(scale_factor_string, &scale_factor))
                display::win::SetDefaultDeviceScaleFactor(scale_factor);
        }
#endif

        if (!GetContentClient())
            SetContentClient(&empty_content_client_);
        ContentClientInitializer::Set(process_type, delegate_);

#if defined(OS_WIN)
        // Route stdio to parent console (if any) or create one.
        if (command_line.HasSwitch(switches::kEnableLogging))
            base::RouteStdioToConsole(true);
#endif

#if !defined(OS_ANDROID)
        // Enable startup tracing asap to avoid early TRACE_EVENT calls being
        // ignored. For Android, startup tracing is enabled in an even earlier place
        // content/app/android/library_loader_hooks.cc.
        if (command_line.HasSwitch(switches::kTraceStartup)) {
            base::trace_event::TraceConfig trace_config(
                command_line.GetSwitchValueASCII(switches::kTraceStartup),
                base::trace_event::RECORD_UNTIL_FULL);
            base::trace_event::TraceLog::GetInstance()->SetEnabled(
                trace_config,
                base::trace_event::TraceLog::RECORDING_MODE);
        } else if (command_line.HasSwitch(switches::kTraceToConsole)) {
            base::trace_event::TraceConfig trace_config = tracing::GetConfigForTraceToConsole();
            LOG(ERROR) << "Start " << switches::kTraceToConsole
                       << " with CategoryFilter '"
                       << trace_config.ToCategoryFilterString() << "'.";
            base::trace_event::TraceLog::GetInstance()->SetEnabled(
                trace_config,
                base::trace_event::TraceLog::RECORDING_MODE);
        } else if (process_type != switches::kZygoteProcess && process_type != switches::kRendererProcess) {
            if (tracing::TraceConfigFile::GetInstance()->IsEnabled()) {
                // This checks kTraceConfigFile switch.
                base::trace_event::TraceLog::GetInstance()->SetEnabled(
                    tracing::TraceConfigFile::GetInstance()->GetTraceConfig(),
                    base::trace_event::TraceLog::RECORDING_MODE);
            }
        }
#endif // !OS_ANDROID

#if defined(OS_WIN)
        // Enable exporting of events to ETW if requested on the command line.
        if (command_line.HasSwitch(switches::kTraceExportEventsToETW))
            base::trace_event::TraceEventETWExport::EnableETWExport();
#endif // OS_WIN

#if !defined(OS_ANDROID)
        // Android tracing started at the beginning of the method.
        // Other OSes have to wait till we get here in order for all the memory
        // management setup to be completed.
        TRACE_EVENT0("startup,benchmark,rail", "ContentMainRunnerImpl::Initialize");
#endif // !OS_ANDROID

#if defined(OS_MACOSX)
        // We need to allocate the IO Ports before the Sandbox is initialized or
        // the first instance of PowerMonitor is created.
        // It's important not to allocate the ports for processes which don't
        // register with the power monitor - see crbug.com/88867.
        if (process_type.empty() || (delegate_ && delegate_->ProcessRegistersWithSystemProcess(process_type))) {
            base::PowerMonitorDeviceSource::AllocateSystemIOPorts();
        }

        if (!process_type.empty() && (!delegate_ || delegate_->ShouldSendMachPort(process_type))) {
            MachBroker::ChildSendTaskPortToParent();
        }
#elif defined(OS_WIN)
        base::win::SetupCRT(command_line);
#endif

        // If we are on a platform where the default allocator is overridden (shim
        // layer on windows, tcmalloc on Linux Desktop) smoke-tests that the
        // overriding logic is working correctly. If not causes a hard crash, as its
        // unexpected absence has security implications.
        CHECK(base::allocator::IsAllocatorInitialized());

#if defined(OS_POSIX)
        if (!process_type.empty()) {
            // When you hit Ctrl-C in a terminal running the browser
            // process, a SIGINT is delivered to the entire process group.
            // When debugging the browser process via gdb, gdb catches the
            // SIGINT for the browser process (and dumps you back to the gdb
            // console) but doesn't for the child processes, killing them.
            // The fix is to have child processes ignore SIGINT; they'll die
            // on their own when the browser process goes away.
            //
            // Note that we *can't* rely on BeingDebugged to catch this case because
            // we are the child process, which is not being debugged.
            // TODO(evanm): move this to some shared subprocess-init function.
            if (!base::debug::BeingDebugged())
                signal(SIGINT, SIG_IGN);
        }
#endif

#if defined(USE_NSS_CERTS)
        crypto::EarlySetupForNSSInit();
#endif

        ui::RegisterPathProvider();
        RegisterPathProvider();
        RegisterContentSchemes(true);

#if defined(OS_ANDROID) && (ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_FILE)
        int icudata_fd = g_fds->MaybeGet(kAndroidICUDataDescriptor);
        if (icudata_fd != -1) {
            auto icudata_region = g_fds->GetRegion(kAndroidICUDataDescriptor);
            CHECK(base::i18n::InitializeICUWithFileDescriptor(icudata_fd,
                icudata_region));
        } else {
            CHECK(base::i18n::InitializeICU());
        }
#else
        CHECK(base::i18n::InitializeICU());
#endif // OS_ANDROID && (ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_FILE)

        base::StatisticsRecorder::Initialize();

#if defined(V8_USE_EXTERNAL_STARTUP_DATA)
#if defined(OS_POSIX) && !defined(OS_MACOSX)
#if !defined(OS_ANDROID)
        // kV8NativesDataDescriptor and kV8SnapshotDataDescriptor could be shared
        // with child processes via file descriptors. On Android they are set in
        // ChildProcessService::InternalInitChildProcess, otherwise set them here.
        if (command_line.HasSwitch(switches::kV8NativesPassedByFD)) {
            g_fds->Set(
                kV8NativesDataDescriptor,
                kV8NativesDataDescriptor + base::GlobalDescriptors::kBaseDescriptor);
        }
        if (command_line.HasSwitch(switches::kV8SnapshotPassedByFD)) {
            g_fds->Set(
                kV8SnapshotDataDescriptor,
                kV8SnapshotDataDescriptor + base::GlobalDescriptors::kBaseDescriptor);
        }
#endif // !OS_ANDROID
        int v8_natives_fd = g_fds->MaybeGet(kV8NativesDataDescriptor);
        int v8_snapshot_fd = g_fds->MaybeGet(kV8SnapshotDataDescriptor);
        if (v8_snapshot_fd != -1) {
            auto v8_snapshot_region = g_fds->GetRegion(kV8SnapshotDataDescriptor);
            gin::V8Initializer::LoadV8SnapshotFromFD(
                v8_snapshot_fd, v8_snapshot_region.offset, v8_snapshot_region.size);
        } else {
            gin::V8Initializer::LoadV8Snapshot();
        }
        if (v8_natives_fd != -1) {
            auto v8_natives_region = g_fds->GetRegion(kV8NativesDataDescriptor);
            gin::V8Initializer::LoadV8NativesFromFD(
                v8_natives_fd, v8_natives_region.offset, v8_natives_region.size);
        } else {
            gin::V8Initializer::LoadV8Natives();
        }
#else
        gin::V8Initializer::LoadV8Snapshot();
        gin::V8Initializer::LoadV8Natives();
#endif // OS_POSIX && !OS_MACOSX
#endif // V8_USE_EXTERNAL_STARTUP_DATA

        if (delegate_)
            delegate_->PreSandboxStartup();

        if (!process_type.empty())
            CommonSubprocessInit(process_type);

#if defined(OS_WIN)
        CHECK(InitializeSandbox(params.sandbox_info));
#elif defined(OS_MACOSX)
        if (process_type == switches::kRendererProcess || process_type == switches::kPpapiPluginProcess || (delegate_ && delegate_->DelaySandboxInitialization(process_type))) {
            // On OS X the renderer sandbox needs to be initialized later in the
            // startup sequence in RendererMainPlatformDelegate::EnableSandbox().
        } else {
            CHECK(InitializeSandbox());
        }
#endif

        if (delegate_)
            delegate_->SandboxInitialized(process_type);

        // Return -1 to indicate no early termination.
        return -1;
    }

    int Run() override
    {
        DCHECK(is_initialized_);
        DCHECK(!is_shutdown_);
        const base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
        std::string process_type = command_line.GetSwitchValueASCII(switches::kProcessType);

        // Run this logic on all child processes. Zygotes will run this at a later
        // point in time when the command line has been updated.
        std::unique_ptr<base::FieldTrialList> field_trial_list;
        if (!process_type.empty() && process_type != switches::kZygoteProcess)
            InitializeFieldTrialAndFeatureList(&field_trial_list);

        base::HistogramBase::EnableActivityReportHistogram(process_type);

        MainFunctionParams main_params(command_line);
        main_params.ui_task = ui_task_;
#if defined(OS_WIN)
        main_params.sandbox_info = &sandbox_info_;
#elif defined(OS_MACOSX)
        main_params.autorelease_pool = autorelease_pool_.get();
#endif
#if defined(USE_AURA)
        main_params.env_mode = env_mode_;
#endif

        return RunNamedProcessTypeMain(process_type, main_params, delegate_);
    }

    void Shutdown() override
    {
        DCHECK(is_initialized_);
        DCHECK(!is_shutdown_);

        if (completed_basic_startup_ && delegate_) {
            const base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
            std::string process_type = command_line.GetSwitchValueASCII(switches::kProcessType);

            delegate_->ProcessExiting(process_type);
        }

#if defined(OS_WIN)
#ifdef _CRTDBG_MAP_ALLOC
        _CrtDumpMemoryLeaks();
#endif // _CRTDBG_MAP_ALLOC
#endif // OS_WIN

#if defined(OS_MACOSX)
        autorelease_pool_.reset(NULL);
#endif

        exit_manager_.reset(NULL);

        delegate_ = NULL;
        is_shutdown_ = true;
    }

private:
    // True if the runner has been initialized.
    bool is_initialized_;

    // True if the runner has been shut down.
    bool is_shutdown_;

    // True if basic startup was completed.
    bool completed_basic_startup_;

    // Used if the embedder doesn't set one.
    ContentClient empty_content_client_;

    // The delegate will outlive this object.
    ContentMainDelegate* delegate_;

    std::unique_ptr<base::AtExitManager> exit_manager_;
#if defined(OS_WIN)
    sandbox::SandboxInterfaceInfo sandbox_info_;
#elif defined(OS_MACOSX)
    std::unique_ptr<base::mac::ScopedNSAutoreleasePool> autorelease_pool_;
#endif

    base::Closure* ui_task_;

#if defined(USE_AURA)
    aura::Env::Mode env_mode_ = aura::Env::Mode::LOCAL;
#endif

    DISALLOW_COPY_AND_ASSIGN(ContentMainRunnerImpl);
};

// static
ContentMainRunner* ContentMainRunner::Create()
{
    return new ContentMainRunnerImpl();
}

} // namespace content
